This invention relates to methods and apparatus for separating solids from liquids, and more particularly to improved methods and clarifiers for separating activated sewage sludge from mixed liquor, and other light flocculant suspensions of solids.
In prior sewage clarifiers employing peripheral downcomers for introducing influent toward their center, it was not always possible to obtain uniform flow distribution, and this reduces process efficiency. When flow rates temporarily or permanently depart from design parameters, severe process upsets can result. Also, changes in inlet flow can disturb the settled sludge blanket or produce eddy currents which cause solids to short circuit the settling tank and flow directly to the effluent weir.